Hunting cap

In electrical and electronic circuits, this phenomenon refers to an unexpected oscillation occurring at a specific frequency due to design defects, wiring faults, or similar issues, causing malfunction. It is synonymous with abnormal oscillation.

In an on-off feedback control circuit, when the controlled variable exceeds the target value and this is detected, the manipulated variable switches from on to off. Then, the controlled variable may fall below the target value. When the manipulated variable is switched from off to on again, the controlled variable may once more exceed the target value. This repeated phenomenon, in which the controlled variable fluctuates up and down around the target value, is referred to as this phenomenon.